riff 1: 
e---------------------------------------
b---------------------------------------
g---------------------------------------
d---------------------------------------
a---2-2-2-3-3-3-2-2-2-3-2-2-5-5-5-5-5---
e---------------------------------------

riff 2:
e-----------------------
b-----------------------
g-----------------------
d---4--3-3-4--3-3-1-1---
a---2--3-3-2--3-3-1-1---
e-----------------------

riff 3:               /p.m.\
e------------------------------
b------------------------------
g------------------------------
d---4--4-----4--4--------------
a---2--2-5-5-2--2-5-5--5-5-5---
e--------3-3------3-3--3-3-3---

riff 4:
e-----------------------
b-----------------------
g-----------------------
d-----------------------
a-------3------3----3---
e---0---3--0---3--0-3---